Knock Sensors
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Knock Sensors Hello All,
To get straight to the point, one of my knock sensors is toast. Had to relocate them to the sides of the block with my 427 transplant. The left bank knock sensor was about 3-4 inches away from the headers, but somehow it still had a melt down, so I'm down one knock sensor. My question is will this affect the operation of the other knock sensor and cause it to not register in the pcm, or will the other one still function until i get the other replaced?
Thanks a lot,
Adrian
To get straight to the point, one of my knock sensors is toast. Had to relocate them to the sides of the block with my 427 transplant. The left bank knock sensor was about 3-4 inches away from the headers, but somehow it still had a melt down, so I'm down one knock sensor. My question is will this affect the operation of the other knock sensor and cause it to not register in the pcm, or will the other one still function until i get the other replaced?
Thanks a lot,
Adrian
Originally Posted by Frost
If the PCM sees a failed sensor it will pull maximum allowed KR when in PE (like 4 degrees) as a safety measure.
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Well, I don't have an SES light, so I dunno wtf haha. I'm running a OL SD tune, so I'm not using the PE table, everything is just run off the VE table and commanded AFR. Plus, I'm not registering any KR, so it appears the PCM is not pulling any timing, unless it won't show it in the log. So, is the other knock sensor still working?
Thanks,
Adrian
Thanks,
Adrian
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They may have to BOTH be damaged to get the 4-deg PE pull; that's how mine were hurt. Look and see if there are any DTCs. What do you mean you don't use PE? Doesn't matter if you are OLSD, CLSD, OLMAF, CLMAF, PE is still in use for WOT enrichment. If you have disabled it you shouldn't have.
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I'll have to check my tune, all of my AFR's are coming from the commanded AFR table, but I don't remember if I have PE enabled or not. Its been a really long time since I've been in my tune (been on deployment). Maybe thats why at some points my commanded AFR goes down to like 10-11 AFR.
Thanks,
Adrian
Thanks,
Adrian
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So, if one knock sensor is out, then the other will not work to detect any detonation and pull timing? Does anyone know for certain? I'm not getting a definite yes or no, and I don't know if the other is working because I don't have any SES lights for the knock sensor.
Thanks again,
Adrian Mejia
PS, I am not using the PE table. Using the PE table is sort of like a middle man to the final commanded AFR. So, I'm just using the Commanded AFR table in this case. I've never had a problem with it before, so really the PE table isn't needed.
Thanks again,
Adrian Mejia
PS, I am not using the PE table. Using the PE table is sort of like a middle man to the final commanded AFR. So, I'm just using the Commanded AFR table in this case. I've never had a problem with it before, so really the PE table isn't needed.
Originally Posted by Haans249
So, if one knock sensor is out, then the other will not work to detect any detonation and pull timing? Does anyone know for certain? I'm not getting a definite yes or no, and I don't know if the other is working because I don't have any SES lights for the knock sensor.
Thanks again,
Adrian Mejia
PS, I am not using the PE table. Using the PE table is sort of like a middle man to the final commanded AFR. So, I'm just using the Commanded AFR table in this case. I've never had a problem with it before, so really the PE table isn't needed.
Thanks again,
Adrian Mejia
PS, I am not using the PE table. Using the PE table is sort of like a middle man to the final commanded AFR. So, I'm just using the Commanded AFR table in this case. I've never had a problem with it before, so really the PE table isn't needed.
YES IT IS. Unless you have fully manually disabled it, it dictates fueling for heavy throttle. If you HAVE disabled it, I'd like to know how you achieve WOT enrichment.
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Actually, its very simple, yes I have manually disabled PE enrichment, because it is not needed. We can argue about it all day, but until you try it, you'll realize that PE isn't needed and is just one less table you'll have to worry about when tuning. You control all of the enrichment you need via the Commanded AFR Table like I said before. Its based on RPM vs MAP, so, when you go heavy throttle (higher MAP values) the PCM will just use the commanded AFR that you setup. So, I get my enrichment by commanding an AFR of 12.8 at higher map values (70kpa up) in the commanded AFR table. Just look at the table and you'll see why PE enrichment is just a waste of your time. Even though PE "dictates fueling for heavy throttle" its not the only table that can accomplish this, and since you have more control over fueling in the Commanded AFR table anyway, its actually better to just use that table instead. So in the end, no, PE enrichment is not needed. There are many nice tricks you can do to make life easier when tuning, and this is one of many. So, its up to you if you want to learn something new, or be stuck in your old ways. Just check out the table, and try it out for yourself, its quite neat! Just make sure you disable PE first so you are actually using the commanded AFR table and not PE. If you want a sample table, send me your tune, and I'll load an example table in there for you. I'm using EFILive. Just shoot me a PM and I'll send you my e-mail address.
And, back on topic, any concrete yes or no on the knock sensor issue? If one is disconnected will the other still register and work?
TIA,
Adrian
And, back on topic, any concrete yes or no on the knock sensor issue? If one is disconnected will the other still register and work?
TIA,
Adrian
By commanded AFR table I guess we are talking about the OLFA table. I don't tune by that table (though I don't leave it quite as the factory has left it either in many cases) because most cars run CL better. I will tune a car in OLSD if the setup is more race oriented or if the owner is willing to periodically bring the car by for checking up maybe once or twice a year, or they have their own software to check up every now and then.
Yes there are many ways to skin a cat, but I don't see the merit in this method for MOST people.
As far as the deal with one sensor going bad; it should still set a code (like low voltage) but from looking at my own car, I don't think it takes action (pulling at PE) until BOTH are bad.
Yes there are many ways to skin a cat, but I don't see the merit in this method for MOST people.
As far as the deal with one sensor going bad; it should still set a code (like low voltage) but from looking at my own car, I don't think it takes action (pulling at PE) until BOTH are bad.
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Originally Posted by Frost
By commanded AFR table I guess we are talking about the OLFA table. I don't tune by that table (though I don't leave it quite as the factory has left it either in many cases) because most cars run CL better. I will tune a car in OLSD if the setup is more race oriented or if the owner is willing to periodically bring the car by for checking up maybe once or twice a year, or they have their own software to check up every now and then.
Yes there are many ways to skin a cat, but I don't see the merit in this method for MOST people.
As far as the deal with one sensor going bad; it should still set a code (like low voltage) but from looking at my own car, I don't think it takes action (pulling at PE) until BOTH are bad.
Yes there are many ways to skin a cat, but I don't see the merit in this method for MOST people.
As far as the deal with one sensor going bad; it should still set a code (like low voltage) but from looking at my own car, I don't think it takes action (pulling at PE) until BOTH are bad.
Yes you are correct, I am talking about that table. It is true that OLSD can be rough, but tuned properly can take a lot of headaches away from a regular CL setup with a larger cam or like you said, race setup etc.. I'm also running a custom operating system through EFILive which allows for fueling adjustments to be made according to different IAT, plus TPS vs RPM VE tuning capabilities, which at that point, have made my large cammed 427 run nearly stock if not better.
Sorry i was late to respond, been gone on mission for the past 3 days. So, what your'e saying is that as long as one knocksensor is running it'll detect knock until both are no longer functioning or I enter PE mode?
Thanks,
Adrian
Originally Posted by Haans249
So, what your'e saying is that as long as one knocksensor is running it'll detect knock until both are no longer functioning or I enter PE mode?
I'm sure to what degree one sensor will cover. I do recall that on my own ride, it didn't start pulling timing whenever in PE until both died. Sorry.